US EPA, Newport, OR OSU dock YSI datasonde dataset from the Pacific Coast Ecology Branch
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Salinity/specific conductance calibration for all field and QA instruments is done using a single point calibration at 10 mS/cm. Depth calibration for field and QA datasondes is done using a single point calibration based on local barometric pressure. Temperature probes are non-adjustable but are checked against a bi-annually factory calibrated temperature meter pre- and post-deployment.
Pre- and post-deployment, temperature and salinity from QA and field data sondes are checked in a lab flow-through seawater bath against a factory calibrated Control Company temperature probe (model 4000) and an in-lab calibrated YSI 556 MPS handheld salinity meter. During deployment, field sonde readings are periodically checked against QA sonde readings just prior to retrieval and manual cleaning of the field sonde sensors. At the end of each sonde deployment QA readings are collected but the field sensors are not cleaned. Final water bath readings and post-deployment sensor checks are performed on sensors in the condition the sonde was collected from the field (potential biofouling organisms are not removed).
“READ ME” sheet:
The first sheet of the datafile include sonde model, deployment depth (sonde height off the bottom), individual deployment file naming format, sonde deployment location in Northings and Eastings (Zone 10, North), and comments related to specific deployment file issues, if applicable. A PVC pipe vertically attached to the OSU pump house dock was used to protect the sonde while in the field. The pipe had several holes (~ 18 – 24) drilled into the lower 1/3 section to allow for tidal exchange.
“Sonde Data” sheet:
The data set, including temperature, salinity, and depth from the OSU dock sonde station, runs from 14 February 2020 to 31 October 2020.
At the beginning and end of each file (unless otherwise noted e.g., battery failure in field) are QA water bath data points or “air readings” (when the instrument was being transported to or from the field). These water bath or air reading are identified in column G cells marked in RED with the word “Out” in those cells. This will be seen at the beginning and, most of the time, at the end of each sonde deployment. “QA” in column G indicates a QA sonde reading collected to compare to deployed sonde data (QA sonde data are in columns I through O). “Deployed” indicates the field sonde was deployed at the field site.
“YSI Compare Deployments” sheet:
The last sheet contains data from the last field point of a previous file compared to the first field point of the subsequent file. This has been done to check for sensor jumps between different sensors/sondes.
Ignore data in rows 23 through 31 as the same sonde was retrieved, post deployment checked, cleaned, recalibrated and redeployed later that same day.
Note:
Negative depth readings indicate there was very little, if any, water above the pressure sensor e.g., an extreme low tide. When the pressure sensor is calibrated its calibration point is based on current barometric pressure. If the pressure is exactly 760 mm Hg the sensor will be calibrated to 0.000 m. If the pressure is above 760 mm Hg the calibration point will be negative. If below 760 mm Hg the calibration point will be positive. Also, the pressure sensors are not vented to the surface so changes in barometric pressure will produce slight changes in pressure reading during deployment.